Method for producing adhesive blanks form an endless band and blanks obtained according to said method

ABSTRACT

The invention relates to a method of producing adhesive die-cut articles with internal cut-outs  3  from an endless web  1,  the web having a carrier layer  4,  at least one adhesive layer  5  and, if appropriate, a matrix layer  6,  and to a die-cut article produced by the method. In order to produce a die-cut article with an internal cut-out  3  while avoiding the use of a hollow punch, the contour  17  of the internal cut-out  3  and the external contour  10  of the respective die-cut article are die-cut out of the adhesive layer  5  and, if appropriate, the matrix layer  6  one after another, the external contour  10  not having any common point with the die-cutting line of the internal cut-out  3,  the carrier layer  4  with the die-cutting residues from the internal cut-out  3  being pulled off over a pull-off edge, and the remaining web being transferred to a protective film  8  (FIG.  1 ).

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a method of producing adhesive die-cut articlesfrom an endless web, having at least one internal cut-out which maycontain a filler material, the web having a carrier layer with at leastone adhesive layer. The adhesive die-cut articles can be single-sided ordouble-sided adhesive sealing rings or labels provided with holes. Theymay also be die-cut articles in the manner of the products obtainablefrom Beiersdorf under the name “Power-Strips”, which are additionallyprovided with a cut-out.

2. Description of the Prior Art

According to the prior art, appropriately shaped cut-outs are introducedinto such objects, to be produced from web material, by means of aso-called hollow punch (also referred to as a complete tool). Thematerial stamped out in the process is forced upwards in the punch.After the cut-out has been stamped out many times, it is necessary tofree the material-filled punch mechanically of the stamped-out material.This entails interruptions to the continuous execution of a process. Afurther disadvantage is the fact that such a complete tool is amechanically sophisticated device, which is therefore quite susceptibleto faults and also expensive.

The adhesive die-cut articles can preferably be locally, regionally orsystemically acting plasters with a backing layer, an adhesive layer anda reservoir of active ingredient which, until they are applied, areprovided with a detachable protective layer.

Forms of medication to be applied to the skin and having the appearanceof traditional plasters are known, containing medicaments which are tobe discharged to the skin and, for example, are known as corn plasters.Such a system can contain one or more medicaments.

SUMMARY OF THE INVENTION

The invention is therefore based on the object of providing a methodwhich permits the production of adhesive die-cut articles with aninternal cut-out, that is, a “hole”, from an endless web, whilstavoiding the use of a hollow punch.

In addition, the invention is based on the object of providing adhesivedie-cut articles with an internal cut-out. A further object of theinvention is to provide adhesive die-cut articles in the form ofplasters which contain active ingredient and have an internal cut-outfilled with filler material.

DESCRIPTION OF THE PREFERRED EMBODIMENT

The object is achieved by a method of producing adhesive diecut articles11 with internal cut-outs 3 from an endless web 1, the web having acarrier layer 4 and at least one adhesive layer 5, which, according tothe invention, is characterized by:

a) die-cutting the contour 17 of the internal cut-out 3 from an adhesivelayer 5 and, if appropriate, from a matrix layer 6, but the carrierlayer 4 not being punched through,

b) die-cutting the external contour of the adhesive die-cut articles 11from the adhesive layer 5 and, if appropriate, from the matrix layer 6this external contour 10 of the adhesive die-cut article not having anycommon point with the contour 17 of the internal cut-out 3,

c) deflecting the carrier layer 4 over a pull-off edge, cut-outdie-cutting residues 7 of the internal cut-out being pulled off togetherwith the unsevered carrier layer 4,

d) transferring the web, freed from the carrier layer 4 and cut-outdie-cutting residues 7 of the internal cut-out, or transferring theindividual die-cut articles, to a protective film 8.

In this case, instead of the pull-off edge 12, a pull-off roller canalso be used, which constitutes a technical equivalent. For the purposeof clarification: the cut-out die-cutting residues 7 constitute thematerial which, after it has been removed from the endless web 1, leavebehind the internal cut-outs 3, that is, the holes, in the said web.

Further steps in the production of the plaster which contains activeingredient and is filled with filler material are:

e) filling the internal cut-out 3 with filler material 2 and laminatingon a covering film 9,

f) die-cutting the contour of the external plaster shape, separating thedie-cut articles and stripping off the die-cutting residues.

The production method according to the invention is surprisinglyuncomplicated, can be carried out without so-called hollow punches andis consequently extremely cost-effective.

One configuration of the method provides for the steps to be carried outin the sequence a) to d), if appropriate as far as f). However,differing from this, it can also be carried out in the sequence b), a),c), d), if appropriate additionally e) and f).

A further simplification is that the steps a) and b) are carried outsimultaneously with each other, for example using a reciprocating punchor a cutting roll. These die-cutting tools then have a surface structurewith cutting edges which have the external contour of the die-cutarticles and the contour of the internal cut-out.

Finally, the operations can be carried out in the sequence a), c), d),b), if appropriate in addition e) and f).

The steps a) to d) can be carried out simultaneously, so that the methodproceeds continuously at constant or variable speed. However, the methodcan also proceed discontinuously, specifically if the use of areciprocating punch makes it necessary to stop the endless web 1.Preference is given to such a discontinuous method if the additionalstep e) is relatively time-consuming.

A further advantageous variant of the method is characterized in thatthe internal cut-out 3 in the adhesive layer 5 is die-cut through thematrix layer 6 and together with the latter.

The geometric shape of the internal cut-out 3 is unimportant. Preferenceis given to a circular shape. The important fact is that the thicknessof the adhesive layer 5 and, if appropriate, of the matrix layer 6 aretogether less than the maximum extent of the internal cut-out 3 in thelongitudinal and/or transverse direction.

An adhesive die-cut article produced by the method is characterized by:

a) an adhesive layer 5 with an internal cut-out 3 and

b) a redetachable protective film 8 which covers the adhesive layer 5and the internal cut-out 3.

In addition, this adhesive die-cut article can have a matrix layer 6.This matrix layer can have an internal cut-out which is congruent with(has an identical two-dimensional shape to) the internal cut-out 3 inthe adhesive layer 5.

The adhesive die-cut article can have a covering layer 9 adhering to theadhesive layer 5 or to the matrix layer 6 located above the latter. Theinternal cut-out 3 can, if appropriate, be filled with a filler material2, which is preferably a compound containing an active ingredient.

Filler materials 2 considered are flowable or pourable preparations,that is to say liquid, semi-solid, gel-like, pasty, powdery or fusiblematerials or mixtures. The ingredients considered are, for example,topically (local and/or regionally) and/or systemically activepharmaceutical active ingredients, including salicylic acid, lacticacid, 5-fluoruracil, capsaicin, acetyl-salicylic acid, nonoic acidvanillyl amide, etc.

Suitable materials for the adhesive layer 5 are natural or syntheticpolymers with contact-adhesive properties, which are known to thoseskilled in the art, for example polyacrylates, polyisobutylenes,silicones, rubber, SIS block copolymers, etc. If necessary, theadhesiveness must be matched to the requirements by the addition ofadhesive resins (“tackyfiers”).

Natural and synthetic polymers are likewise preferably considered forthe matrix layer 6, such as polyacrylates, polyethylenes,polypropylenes, polybutylenes, polyurethanes, poly-l-butenes,polyisobutene, rubbers, silicon rubbers, cellulose, chemical pulp,paper, cotton, acetylcellulose, celluloid, viscose, polyacrylonitrile,polyvinyl alcohol, polyvinyl acetate, polyvinyl ether, ethylene-vinylacetate copolymers (EVA) and the like. These materials, and consequentlythe matrix layer 6, are non-adhesive. They may be present as a compactedmaterial, foam, fabric, porous sheet, nonwoven fabric, etc.

The method and the apparatus provided for implementing it areuncomplicated, comprehensible and surprisingly effective in functionalterms. To this extent, the invention achieves the object set at thebeginning in an optimum way.

Further details, features and advantages of the invention emerge fromthe following exemplary embodiments and the drawings shown.

EXAMPLE 1

Production of a Filled Die-cut Article

During the continuous production of the adhesive die-cut articles 11from an endless web 1, the latter is first moved in the direction of thearrow 13 into a die-cutting station 15, in which the contours 17 of theinternal cut-outs 3 from at least the adhesive layer. 5 are punchedthrough, but without the carrier layer 4 being punched through at thesame time. In the example shown, there is, a further, optional layer,namely the matrix layer 6, on the adhesive layer 5. In the presentexample, both the matrix layer 6 and the adhesive layer 5 are punchedthrough in the die-cutting station 15, but the cut-out die-cuttingresidue 7, that is, the “die-cutting core”, initially still remainingwithin the contour 17 of the internal cut-out 3. Suitable die-cuttingstations 15 are either a reciprocating punch, which permits a procedurewith the web being stopped, or a rotating cutting roll, which permits avariable or constant web speed without the web being stopped. Ahigh-energy laser beam, which moves over the contour 17 of the internalcut-out 3, can likewise carry out the technical function of thedie-cutting station 15.

During further transport in the direction of the arrow 13, the externalcontour 10 of the die-cut articles 11 is then cut out of the matrixlayer 6 and the adhesive layer 5 in the second cutting station 18, theexternal contour 10 of the said layers not having any common point withthe contour 17 of the internal cut-out 3. A die-cutting grid which maybe produced in the process is “stripped off”. The previously die-cutendless web 1 then reaches the pull-off edge 12, at which the carrierlayer 4 which has not been stamped through is pulled off together withthe cut-out die-cutting residues 7.

The die-cut articles prepared in this way are immediately subsequentlytransferred, by a roller (19), to a protective film 8, the underside ofthe adhesive layer 5 being covered by the protective film 8.

During further transport of the die-cut-contour die-cut articles withinternal cut-outs 3 still open (that is to say not covered and notfilled), these reach a position underneath the filling station 16, whichin each case puts a meterable portion of filler material 2 into theinternal cut-outs 3 which have until now been open. After that, duringfurther transport, a covering film 9 is laminated on to the die-cutarticles from above in a laminating station 20.

EXAMPLE 2

Production of a Filled Die-cut Article

As Example 1, but the die-cutting of the external contour 10 of theadhesive die-cut article 11 is carried out after the filler material 2has been put in, that is to say the second cutting station 18 (showndashed in FIG. 1) is located downstream of the filling station 16 andlaminating station 20.

EXAMPLE 3

Production of an Unfilled Die-cut Article

As Example 1, but the die-cutting of the contour 17 of the internalcut-out 3 and of the external contour 10 of the adhesive die-cut articleare carried out simultaneously in a rotational cutting roll. Owing tothe geometric shape of the external contour of the die-cut article, nodie-cutting grid occurs in this case. Stripping off is therefore notnecessary. During the subsequent transfer of the previously die-cutarticles to the protective film 8, they are separated, since thisprotective film has a higher web speed than the endless web 1. Nofilling of the internal cut-out 3 is carried out.

EXAMPLE 4

Production of a Plaster Containing Active Ingredient

The production of a plaster containing active ingredient is carried outon a flat-bed punch which is equipped with the following units:

second plane with die-cutting station

laminating device

metering station

format die-cutter

cross-cutter

packaging unit with heat-sealing punch (in the case of on-linepackaging)

The protective film is drawn into the machine. On a second plane, thepolyethylene foam laminate is fed to a die-cutter, which cuts out theholes to be filled with active ingredient compound. The intermediatecovering paper with the die-cut foam adhering to it is pulled off. Theperforated foam is laminated on to the protective film and filled withactive ingredient compound in the metering station. After theintermediate covering paper has been removed from the laminate, theadhesive-coated, skin-coloured polyethylene film is laminated on to thefoam.

The contour of the plaster is stamped from above into this laminate,consisting of protective film, adhesive, foam with active ingredientcompound, adhesive and skin-coloured polyethylene film, by means of aflat-bed punch with a strip-steel cut. Excess polyethylene film and foamare pulled off upwards, the individual plasters remaining stuck to theprotective film. Following cross-cutting, the plasters are sealed intwos into packaging material.

EXAMPLE 5

Production of Adhesive Die-cut Articles with a Rectangular InternalCut-out

An endless web consisting of a laminate (containing a polyethylenematrix 0.9 mm thick, a polyacrylate adhesive layer 50 μm thick and asiliconized paper carrier layer) with a width of 3 cm is led into arotational cutting roll, which stamps out rectangular internal cut-outs3 1.6 cm long and 6 mm wide. At the same time, this cutting roll stampsa cut at 6 cm intervals into the endless web, specifically in such a waythat the internal cut-out 3 is located at the centre of the previouslydie-cut articles. Stripping off is not necessary, since there is noprojecting edge between the die-cut articles or at their lateralboundaries. The previously die-cut articles are freed from the carrierlayer 4 and the cut-out die-cutting residue 7 at a deflection roller. Asthey are transferred to the siliconized polyethylene terephthalateprotective film 8, running at a higher speed, spacings of 1 cm areproduced between the separated die-cut articles.

DESCRIPTION OF THE FIGURES

FIG. 1 shows the schematic diagram of an apparatus for implementing themethod of producing adhesive die-cut articles from an endless web.

FIG. 2a shows, in a section in the plane II—II, the endless web 1composed of the carrier layer 4, the adhesive layer 5 and the matrixlayer 6.

FIG. 2b shows a web 1 consisting of carrier film 4 and adhesive layer 5.

FIG. 3a shows, in a section in the plane III-III, the structure of theadhesive die-cut articles 11 after the die-cutting of the contours 17 ofthe internal cut-outs 3 and of the external contours 10, and after thefilling of the internal cut-outs 3 with filler material 2 and afterlaminating a covering film 9 on.

FIG. 3b shows a die-cut article, consisting of an adhesive layer 5 andcontaining the internal cut-out 3, on the second carrier film 8, withoutany filler material.

FIG. 4a shows, in plan view, die-cut articles 11 within the externalcontours 10, with die-cutting contours 17 of the internal cut-outs 3 andthe filler material 2 contained in the internal cut-outs 3. The die-cutarticles 11 are still located within the endless web 1, before beingseparated.

FIG. 4b shows a plan view of adhesive die-cut articles 11 in which theinternal cut-out 3 is not filled.

The invention has been described with particular emphasis on thepreferred embodiments, but variations and modifications within thespirit and scope of the invention may occur to those skilled in the artto which the invention pertains.

What is claimed is:
 1. Method of producing adhesive die-cut articleswith internal cut-outs from an endless web, the web having a carrierlayer and at least one adhesive layer, comprising the following steps:a) die-cutting a contour of the internal cut-out from the adhesivelayer, but the carrier layer not being punched through, b) die-cuttingan external contour of the die-cut articles from the adhesive layer,this external contour not having any common point with the contour ofthe internal cut-out, c) deflecting the carrier layer over a pull-offedge, resulting in cut-out die-cutting residues of the internal cut-outbeing pulled off together with the carrier layer, d) transferring theweb, freed from the carrier layer and the cut-out die-cutting residues,to a protective film.
 2. Method according to claim 1, comprising thefurther step of: e) filling the internal cut-out with filler materialand laminating on a covering film.
 3. Method according to claim 1wherein said adhesive die-cut articles are in the form of plasters whichcontain active ingredients, comprising the further step of: f)die-cutting the contour of the plaster, separating the die-cut articlesand stripping off the die-cutting residues.
 4. Method according to claim1, wherein the steps are carried out in the sequence a) to d).
 5. Methodaccording to claim 1, wherein the steps are carried out in the sequenceb), a), c) and d).
 6. Method according to claim 1, wherein the steps a)and b) are carried out simultaneously.
 7. Method according to claim 1,the endless web containing a carrier layer, an adhesive layer and amatrix layer wherein the internal cut-out in the adhesive layer isdie-cut through the matrix layer and together with the latter.
 8. Methodof producing adhesive die-cut articles with internal cut-outs from anendless web, the web having a carrier layer and at least one adhesivelayer, comprising the following steps in the following sequence: a)die-cutting a contour of the internal cut-out from the adhesive layer,but the carrier layer not being punched through, b) deflecting thecarrier layer over a pull-off edge, resulting in cut-out die-cuttingresidues of the internal cut-out being pulled off together with thecarrier layer, c) transferring the web, free from the carrier layer andthe cut-out die-cutting residues, to a protective film, and d)die-cutting an external contour of the die-cut articles from theadhesive layer, this external contour not having any common point withthe contour of the internal cut-out.